Mark when we may have been invalidated to early out on repaintTreeAfterLayout.

Source/core/rendering/RenderLayer.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 481 matching lines @@
 
     if (renderer()->style()->hasViewportConstrainedPosition())
         flags |= HasSeenViewportConstrainedAncestor;
 
     if (renderer()->hasOverflowClip())
         flags |= HasSeenAncestorWithOverflowClip;
 
     if ((flags & IsOverflowScroll) && (flags & HasSeenAncestorWithOverflowClip) && !m_canSkipRepaintRectsUpdateOnScroll) {
         // FIXME: We could track the repaint container as we walk down the tree.
         repainter().computeRepaintRects(renderer()->containerForRepaint());
+        renderer()->setMayNeedInvalidation(true);
     } else {
         // Check that RenderLayerRepainter's cached rects are correct.
         // FIXME: re-enable these assertions when the issue with table cells is resolved: https://bugs.webkit.org/show_bug.cgi?id=103432
         // ASSERT(repainter().m_repaintRect == renderer()->clippedOverflowRectForRepaint(renderer()->containerForRepaint()));
     }
 
     for (RenderLayer* child = firstChild(); child; child = child->nextSibling())
         child->updateLayerPositionsAfterScroll(geometryMap, flags);
 
     // We don't update our reflection as scrolling is a translation which does not change the size()
@@ skipping 422 matching lines @@
         return has3DTransform() || m_has3DTransformedDescendant;
 
     return has3DTransform();
 }
 
 bool RenderLayer::updateLayerPosition()
 {
     LayoutPoint localPoint;
     LayoutSize inlineBoundingBoxOffset; // We don't put this into the RenderLayer x/y for inlines, so we need to subtract it out when done.
 
+    renderer()->setMayNeedInvalidation(true);
+
     if (renderer()->isInline() && renderer()->isRenderInline()) {
         RenderInline* inlineFlow = toRenderInline(renderer());
         IntRect lineBox = inlineFlow->linesBoundingBox();
         setSize(lineBox.size());
         inlineBoundingBoxOffset = toSize(lineBox.location());
         localPoint += inlineBoundingBoxOffset;
     } else if (RenderBox* box = renderBox()) {
         // FIXME: Is snapping the size really needed here for the RenderBox case?
         setSize(pixelSnappedIntSize(box->size(), box->location()));
         localPoint += box->topLeftLocationOffset();
@@ skipping 3056 matching lines @@
     }
 }
 
 void showLayerTree(const WebCore::RenderObject* renderer)
 {
     if (!renderer)
         return;
     showLayerTree(renderer->enclosingLayer());
 }
 #endif